1. Field of the Invention
The present invention relates to an ultrasonic diagnostic apparatus which transmits ultrasonic waves from an ultrasonic probe, which comprises a plurality of ultrasonic transducers arranged in a specified shape, into a subject, receives ultrasonic waves reflected in the subject with a plurality of transducers, enters these ultrasonic waves into a delay control circuit, which respectively applies a corresponding delay time control or a delay time control and a phase control to received signals obtained therefrom and appropriately adds the modification signals to each other, and displays an internal image of the subject in accordance with additive signals outputted from the delay control circuit and more particularly an improvement of the delay control circuit of this ultrasonic diagnostic apparatus.